User Guide

ACDSee Pro 2.5 - User Guide
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Using the Advanced tab
Sliders
The Advanced tab has two sliders for brightening and
two for darkening, called Compression and Amplitude.
The Compression sliders control the shape of the
brightening/darkening adjustment curves, while the
Amplitude sliders control the height of the curves.
The more compression you apply, the more you
increase the balance of the dark against the light
areas in the image. The Amplitude sliders increase
the intensity of the effects of brightening or
darkening.
The Scale slider at the bottom of the tool, adjusts the
overall adjustment sensitivity to local variation in
brightness. Moving this slider to the left makes the
adjustment more sensitive to smaller areas of
brightness variation, which may be beneficial in some
images. For most images, however, leaving the slider
in the default position gives the best result.
Checkboxes
You can individually disable Brightening or Darkening completely by deselecting the
checkboxes. This is useful when you want to preview the effect of brightening or darkening
individually.
Graphs
Between the Brighten and Darken controls are two gray graphs that indicate the maximum
amount of lightening or darkening that you can apply before clipping (shown as bright
pink) begins.
Two orange curves appear and change as you drag the Compression sliders and Amplitude
sliders - these curves indicate the amount of brightening and darkening applied throughout the
tonal range of the image. Darker tonal areas are on the left, and brighter tonal areas are on
the right. As you move your cursor over the image, a vertical line in the graph indicates the
tone level of the area under the cursor within the tonal range. At times there are two lines
because the tone levels for brightening and darkening are not necessarily the same. This is
because brightening is sensitive to maximum color values while darkening is sensitive to
minimum color values
The Advanced tab is unique in that you can adjust the curves manually, either on the graph
itself, or on the actual photo. Adjustments made on the photo are reflected in the curve on the
graph. Adjustments made on the graph are reflected on the photo.
To increase contrast within a tonal range without changing the brightness, apply brightening
and darkening simultaneously in equal amounts by dragging the upper and lower curves up and
down, respectively. The area between the top of the upper graph and the bottom of the lower
graph indicates the amount by which contrast is increased.